Cyber security firm KPMG has warned that Google’s self-driving cars could pose a new kind of threat on the roads, and be vulnerable to hackers.

The firm has said that the industry must be alert to the risk of “cyber manipulation and attack” and that hackers could conspire to create “spam jams”.

Given self-drive cars are internet connected they could be vulnerable to having large volumes of online traffic manipulated so that the websites are overwhelmed, creating these spam jams and creating major disruptions.

The firm has called for manufacturers to build safety features in to lessen the risk of this happening.

Earlier this week Google revealed that it has built a prototype of a self-driving vehicle, and is to start manufacturing its own cars, rather than continuing to modify its fleet of Lexus and Honda vehicles.